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<h3>Tips for Writing Extensions</h3>

<p>An Extenders Guide will be published in the future. At the moment, writing an
extension is a bit of an adventure. Extension authors are advised to join the 
nunit-developer list and post questions and comments there.

<p>For the moment, the following tips may be of assistance.
<ul>
<li>The <b>nunit.core.interfaces</b> assembly is intended to be stable in the future
while the <b>nunit.core</b> assembly will change from release to release. Right now,
both assemblies are still in flux, but extensions that depend solely on the interfaces
assembly will have a much better chance of surviving NUnit version changes. Unfortunately,
this is rather difficult to do without duplicating a great deal of NUnit code. Most
of the add-in samples provided with NUnit are currently version dependent.

<li>If you place the definition of a custom attribute in the same assembly as your
add-in, then user tests are dependent on the add-in assembly. If the add-in is 
version-dependent, then the user tests will also be version-dependent. We suggest
placing any types referenced by user tests in a separate assembly, particularly if
your extension relies on nunit.core.

<li>If using Visual Studio, set Copy Local to false for any references to nunit.core
or nunit.core.interfaces. This is especially important if you are also building
NUnit itself.

<li>There is currently no mechanism to allow decorators to apply in a particular order.
NUnit applies decorators in the order in which they are returned through reflection,
which may vary among different runtimes.

<li>Avoid trying to "stretch" the existing extension points to do more than they were
intended to do. Rather, let us know what further extension points you would like to see!
</ul>


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